The use of pyrolysis as a means of recovering oil and carbon byproducts by combustion of waste material under vacuum is well-known. An application of this process is described in “The Vacuum Pyrolysis of Used Tires and Uses for Oil and Carbon Black Products by C. Roy, A. Chaala, and H. Darmstadt—Elsevier Journal of Analytical and Applied Pyrolysis Vol. 51 (1999) p. 201-221” which paper is incorporated into this specification by this reference.
The conventional pyrolytic process involves shedding biomass material into small chips or debris that are then pyrolyzed under a controlled atmosphere. A common method consists of spreading the debris over a conveyer belt that passes through a high temperature furnace. Debris may also be incinerated by mixing them with super-heated sand. The pyrolyzed material is then treated chemically or mechanically to extract desired bi-products. The prior art methods require multi-step treatment, including pre-shredding of large articles, through complex equipment at a relatively slow throughput rate.
This invention results from an attempt to devise a simple and more efficient method and apparatus to recover large quantities of useful byproducts from the pyrolysis of a large variety of biomass waste material.